Fifth generation (5G) wireless standards specify signals in a millimeter wave (mmW) band (e.g., around 28 gigahertz (GHz)) that is about 10 times higher than the frequencies typically used for cellular communication. A wireless communication apparatus (e.g., smartphone) operating in, or around, this mmW band may require a substrate integrated waveguide (SIW) for guiding and/or processing mmW signals in this band.